Centrifugal blower



lll l llllllllll HIHII lllll mill ll /III VII will @I IIIIIII w; E.TRUMPLER ,CENTRIFUGAL BLowER Filed May s, 1'931 May 10, 1932.`

-Patented May Il), 1932' UITEDSTATES -PATENrfol-FICE i wxLLumi nm'aUuPLnn, or nnsroN, rnNNsYLvnNn, `essIeNon. To mcnnsommn CMIRAEI'Y',l0F JERSEY CITY, NEW JERSEY,

A `CORPORATION OF NEW JERSEY' cniv'rmuear. Brom Application Med lay l8,1931. Serial' No. 535,838.

This invention relates to multi-stage centrifugal blowers, compressorsand the like, and more particularly to a diaphragm interposed betweenstages aof apparatus of this character.

One object of the invention is to avoid un-v due acceleration andconsequent pressure loss between stages.

f Another object is-to assure a comparativel l0 direct path off/flow forthe fluid from a di user chamber into the guideways leading to theeye ofa succeeding stage impeller.

Other objects willbe in partobvious and in part pointed out hereinafter.

In the drawings laccompanying this 'speciication and forming a partthereof,

Figure 1 is a sectlonal elevation of aportion of a centrifugal blowerequipped with a diaphragm constructed in accordance with 20 'thepractice of the invention,

Flgure 2 1s a transverse view takenthrough Figure 1 on the line 2 2looking in the direction indicated by the`arro`ws, and Figure 3 is a topplan view of the dia- 25 phragm. i c

Referringmore particularly to the drawings, the blower which isdesignated nercasing A is of larger diameter than-the impellers K' and Land the impellers are suitably spaced along the length of the shaft J toc permit the arran ment between adacent impellers of dialragms O whichare `so spaced with respect to each other as to form therebetweendiffuser chambers P into which the fluid charged. f

Each diaphragm O constructed in accordance with the practice of theinvention ma consist of upper and lower half-sections 4he sections Q andR and R respectively.

pumped by the impellers is disma be identical in all t eir essentialrespects an comprise outer and inner walls Sand TA which are connectedtogether by vanes U, shown in this instance as being of'involute `shapeto form correspondingy sha d guideways V through which the uid ows fromthe diffuser chamber P to the eye W of a succeeding stage impeller.

In order that the fluid-may flow from the diiuser chamberP into theadjacent guide- 'ways V' along a path of minimum tortuosity the wall Sis provided with suitable notches or recesses X which are denedb a.portion Y of the peripheral 4surfaces of the vanes U comparing the,present "structure with diaphragms as heretofore constructed and in 1which a pair of circular walls of different diameterv are held in spacedrelation by vanes disposed therebetween to form guideways through whichlthe fluid flows from the diiuser'chamber to a succeeding stageimpeller.f

In blowers'as at present constructed, however, the wall of smallerdiameter and which wouldtherefore correspond to the Wall S of thepresent structure, being circular and extending with its periphery to atleast the outer Vends' of the vanes, requires rthat the pressure fluidmake an abrupt or right-angle turn, to pass thereover to the inlet'opening of the guideways and therefore a second right-angle turninentering the guideways. The fluid must, in view of this arrangement,follow an extremel tortuous'fpathL from the diffuser chambers into theguideways with consequent undesirable acceleration and considerablepressure loss. This is of course highly objectionable in apparatus Iofthis character and in which, unlike compressors of the reciprocatorytype, the pressure of the Huid is not increased by very substantialvalues in individual stages.

. As `is of 'course well known, owing tothe work of compression thetemperature of the fluid increases progressively duringits passagethrough the several stages of the blower. In' other words,`thetemperature of the fluid flowing through the diffuser chamber P as-vsociated with the impeller K and which, for this purpose,'may beconsidered as being the first stage impeller, is increased considerablyabove atmospheric temperature, and the temperature is again increasedduring the pas-4 sages ofthe fluid through the impellerL and itsdiffuser chamber P. f

Unless effectively restrained the heat of the fluid of higher value willbe transmitted to adjacent guideways and diffuser chambers and beabsorbed lby the fluid flowing therethrough, thus 4causing areduction'in'the efciency of the blower. y i.

In view .fof the foregoing facts it is contemplated to insulate theguideways V from the diffuser chamber P of a succeeding stage. To thisend the diaphragm O is rovided with an additional wall e to form aounding surface for the' diffuser chamber P associated with thesucceeding stage impeller, as for instance the impeller L., The wall e,which is connected at its ends with the wall T, is suitably spaced withrespect to the wall T to form therebetween an annular insulating'chamber f which may be either an air pocket or, as shown, may be usedas a water jacket to effect an additional cooling of the fluid flowinfrover the walls T and e.

n order to render the space f capable for use as a water jacket thediaphragm is providedy in its periphery with a port gv throu h which swater may be introduced into tie chamber f. Such water may be conveyedto the chamber f by a connection h threaded into the casing A andcommunicating with a groove j in the periphery of the diaphragm 0.

Preferably the diaphragm O is provided on its periphery with a pair ofribs k which are located on opposite sides of the groove j and extendinto an internal oove o in the casing A to conveniently maintain thediaphragm O in the proper position relatively to the impellers K and L,and also to effect a suitable fluid tight joint at this point betweenadjacent dilfuserchambers,

In practice, the present invention has been found to be extremelyeilicient. By means of the arrangement described a comparatively directpath has been provided for the fluid from the diffuser chamber P intothe guideways No portion of the path followed by the fluid from thedifuser chamber to a succeeding stage impeller is restricted and, as aresult thereof, the conversion of the velocity of.the luid'into pressuremaybe elliciently brought about. Moreover, by insulating the gudeways Vfrom the comparatively high temperature prevailing in the diffuserchamber of a succeeding stage, the temperature of the fluid-flowingthrough the guidewaysis in no wise increase above the value containedupon the discharge of the iuidfrom theimmediately preceding stageimpeller.

1. A multi-stage centrifugal blower including a plurality of impellers,diffuser chambers vto receive the fluid from the impellers, a diaphragmbetween adjacent impellers, vanes on the diaphragm forming guidewaysto`convey fluid from a diuser chamber to a succeeding stage impeller,and a wall forming a closure for one side of the guideways and havingnotches through which fluidl flows to the inlet openings of theguideway's.

2. A'multi-stage centrifugal blower -including a plurality of impellers,diffuser chambers to receive the fluid from the im- 'pellers, adiaphragm between adjacent impellers', vanes on the diaphragm 'formingguideways to convey Huid from a' diffuser chamber to a succeeding stageimpeller, and a wall forming a closure for one side of the guideways andhaving portions of its periphery coincident with portions of the outersurfaces iof'the vanes, said wall having stepped portions extending fromthe outer ends of the asuman vanes to intermediate portions of adjacentvanes.

3. A multi-stage centrifugal blower including a plurality of impellers,diffuser chambers to receive the fluid from the impellers, a diaphragmbetween adjacent impellers, vanes on the diaphragm forming guideways toconvey'luid from a diffuser chamber to a succeeding stage impeller, anda wall formin a closure for one side of the guideways am? havingrecesses therein to enable Huid to flow over intermediate portions ofthe vanes to the inlet openings of adjacent guideways.

4. A multi-stage centrifugal blower in cluding a plurality of impellers,diffuser chambers to receive the duid from the impellers, a diaphragmvbetween adjacent impellers, vanes on the diaphragm forming guideways toconvey fluid from a diffuser chamber to a succeeding stage impeller, a.wall forming a closure for one side of the guideways and having recessestherein to enable Huid to flow over intermediate portions ofthe vanes tothe inlet openings of adjacent guideways, and means on the diaphragm toform an insulatin chamber be- .tween the guideways and a di userchamber.

In testimony whereof I have signed this specification.

' WILLIAM E. TRUMPLER.

